The 2SA1477 part number names this 135 KB PDF, which is filed as a schematic but should be a component data sheet. JIS numbering places 2SA devices in the PNP transistor family. No maker, package or version appears in the name. Expect ratings, electrical characteristics and likely characteristic curves. Technicians use it to identify pins, check voltage and current headroom for a substitute and recognise the part from its package. Confirm the board marking corresponds to this number.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @cyberlanelectonik. Enginerys does not host this file.
How to open a .pdf file
The standard format for schematics, block diagrams, power-sequence charts and service manuals.